Either way for me...I play mostly sitting down at practice or while recording. If I sit down however I still use the strap.
Once ( many years ago) I bought an instructional video by Billy Sheehan, and while I did not care much for it, there was one piece of advice in it that I never saw anywhere else. He commented about how often in his touring he would come across other bass players, who absolutely rocked while warming up backstage, and kinda sucked during the actual performance on stage, and proceeded to blame the sound man or someone else for their poor performance. His observation was that all these cats practiced sitting down and got really good at whatever they practiced; the problem he noticed was that while sitting down, the bass was in a totally different place than when they played standing up. So, of course, once they got on stage nothing was where they were used to and their proficiency suffered.
His advice was that, standing up or sitting down, you should wear a strap and make sure your instrument is pretty much in the same position, otherwise your sit-down practice won't be as useful to your playing when it's time to stand up.
Valentino
(Message edited by valvil on November 04, 2003)